Dishwashing machine



April 7, 1942. T. E. D. BILDE DISHWASHING MACHINE Filed Feb. 14, 1940 6' Sheets-Sheet" l 19 CLAN my April T. E. D. BILDE 2,278,823

DISHWASHING MACHINE Filed Feb. 14, 1940 6 Sheets-Sheet 2 Invenior:

April 7, 1942 B|| DE 2,278,823

DISK- WASHING MACHINE Filed Feb. 14, 1940 6 Sheets-Sheet 3 Inaeni'o r:

April 7, 1942.

T. E. D. BILDE DISHWASHING MACHINE 6 Sheets-Shet 4 Filed Feb. 14, 1940 f 2: 1mm

April 1942- T. E. D. BI| ..DE 2,278,823

DISHWASHING MACHINE Filed Feb. 14, 1940 6 Sheets-Sheet 5 r V M @696 Znuen Zor: 25rd 16?;(35 Daniel Bjcld, By

April 7, 1942- DISHWA$HING MACHINE Filed Feb. 14, 1940 4 s Sheets-Sheet 6 lnueni'or:

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T. E. D. BILDE 2,278,823 7 Patented Apr. 1,1942

DISHWASHING MACHINE Tord Erik Daniel Bilde, Ulvsunda, Sweden,- assignor to Bolinders Fabriks Aktiebolag, Stockholm, Sweden, a corporation of Sweden.

Application February 1 In Germany 4, 1940, Serial No. 318,928

March 2, 1939 s oiaims. (01. 103-25) The present invention relates to dish washing machines which are provided" with a pump or pumps for forwarding a liquid or liquids serving for cleaning the dishes and with an electric motor for driving said pumps.

, In dish washing machines of this type it is t e most obvious proceeding to make the'means for setting; the valve or valves and the means for setting the 'switch controllable independently of each other. In doing this, however, these means must be operated in a definite sequence relatively to one another in order to ensure a safe operation' of the machine. For, example, if the valve setting means is actuated whilst the motor and accordingly the pump, are till in operation the setting of the valve will be ren-I dered more diflicult or even impossible, as a relatively' large expenditure of energy is necessary in order to overcome the pump pressure which not infrequently is high, The operation of the machine presupposes under such circumstances a certain expert knowledge, which it is sought to avoid, however, as the operation of suchmachines is usuall-y'entrusted to more or less un skilled persons. v

The principal object of the invention is to eliminate these difficulties and to provide a dish washing machine of the type described in which i the valve or valves'and the switch are positively controlled so 'as to permit their operation only .1

in the correct sequence, thereby ensuring an auto matic and safe operation of the machine.

- Another object of the invention is to provide a dish' washing machine of the type described in which the means for setting the valve or valves and the means for setting-the switch are so combined with each other that actuation of the valve setting means is prevented, when the motor is switched-on, and permitted only when the switch is set to open the circuit of the motor. Preferably the connection of the valve setting means and the switch setting means are such that in addition to the above said blocking of the valve setting means, when the motor is switched-on, actuation of the switch setting means to close the circuit switch on themotor is prevented when the valve is closed and permitted only when the valve setting means is set to open the valve.

These and further objects of the invention will f be apparent according as the following description proceeds, reference being had to the ac-' companying drawings in which:

Figs. 1 and 2 represent two different positions of setting of two knobs arranged to operate the valve setting means and the switch, respectively, the said knobs mutually blocking one another according to the invention.

.Fig, 3 is a side elevation, partly in section, of a dish washing machine arranged according to the invention.

Fig. 4 is a front elevation of this machine, also partly in section.

Fig. 5 is a sectional view of a control box.

Figs. '6 to 8 represent a switch in various positions.

Fig. 9 illustrates a thermostat and the connection thereof to the switch.

Fig. 10 is a cu'rrentdiagram.

Fig. 11 shows a modification of the machine according to Figs. 3 and 4.,

In Figs. l and 2, l0 represents a knob foroperating the switch of an electrically operated dish washing machine, and I l a knob for operatin two valves of the machine, which is provided with two pumps each controlled by one of these valves for washing or rinsing liquid, respectively. p The spindles l2 and Id of the knobs carry each a disk 15 and I6, respectively, which disks are of equal diameter. The distance between the centres of thedisks is less than their diameter and the disks are provided withrecesses of a shape as to make both of the disks freely mov; able when a recess in one of the disks is opposite a recess in the other disk. The disk l5 has one recess 11 and the disk It two recesses l8 and 19 corresponding each to open position of one of the valves; In the position according to Fig. 1, corresponding to switched-out motor and closed valves, knob It), as will be seen, cannot be set, or in other words, the motor cannot be switched-on, whereas knob H on the other hand is freely settable. Knob l0 can only be set, or in other words, the motor switched-on when knob I l is turned in one direction or the other through such an angle that one of the recesses I8 or I9 is opposite the recess vll, that is to say one of the valves has been opened. In this position of the knobs which is represented in Fig. 2, knob l0 can be freely set whilst knob I l is looked, that is the valves cannot be set, such' settin of the valves becoming possible only when knob I0 is re-set into the rest position according to Fig. l in which the motor has been switched-off.

In the embodiment represented in Fig. 3the 1- locking disks 22 and 23 mounted on the spindles 20 and 2 l of two-knobs for the operation of the tween the-disks is a tube in which two plungers 21 and 28 can move, said plungers being mounted in bearings outside the tube at 29 and 38, respectively, and each capable of engaging one of the recesses. A spring 3| arranged in the tube 26 between the two plungers presses them outwards against the corresponding disk.

In the figure both of the blocking disks are represented as -being in their rest position. If, for example, the knob mounted on the spindle 20 is turned, plunger 21 is pushed inwards of the tube causing compression of spring 3|. An abutment 21a on plunger 21 moves loose tube 26 against plunger 28 and an abutment -28a on it, whereby' plungers 21, 28 and tube 28 form a rigid blocking unit for disk 23. Thus, in their rest position the blocking disks 22. 23 are only elastically blocked and any one of them can be .freely turned in one direction or the other, but if a blocking disk has been turned out of its rest position,'the

other disk will be positively blocked in such a way, that its turning is prevented. Also in this case the knobs control a switch or one or more valves, respectively. I

In Figs. 1 and 2 the connections between the knobs and the switch or the val setting means, respectively, ar not shown. I gy can be of any desired form or' design and consist, for example, of ropes. rods etc.

The dish washing machine as shown in Figs.

3 to 10 will first be described in respect of its general design b reference to Figs. 3 and 4.

40 indicates a housing built in a washing bench 4| and supported by an upper flange 42 on a shoulder 43 provided around an opening in the top panel of 'the bench. The housing is closed at th top by a lid 45 connected to the housing by hinges 44 and lying, when in its closed position, in flush with the upper surface of the bench.

The housing forms a spraying chamber 48 for the dishes and at its bottom it is formed to provide a reservoir which is divided by two sloping walls 41, 48 into two compartments, on 49 for washing liquid and the other 58 for rinsing liquid. A motor pump unit consisting of an electri'c motor 5| and pumps 52. 53 arranged on either side of the motor is arranged underneath the spraying chamber 48 and behind the liquid reservoir. A suction pipe 54 for pump 52 is connected to an orifice at the bottom of the washing com-' partment 48 and controlled by a lift valve 55. the valve rod 56 of which passes through the wall of pipe 54. A suction tube 51, lift valve 58 and' valve rod 58 of pump 53 are arranged in similar fashion with regard to the rinsing liquid compartment 50. At the lowermost point of the washing pump 52 is a discharge pipe 60 controlled by a valve (not shown). the rod 8! of which is conducted through the wall of the discharge pipe 60. 62 is an overflow pipe leading from the washing compartment 48.

The washing pump 52 is connected through a,

rising pipe 63 to a spraying device for washing liquid. which consists in this case of a spray pipe 64 swingable horizontally to and fro in the lower part of the spraying chamber. A similar rising pipe connects rinsing pump 53 to a spraying device for rinsing liquid, comprising a fixed spray pipe 66 arranged in the lower part of spraying chamber 46.

61 designates a control box enclosing all the electrical members of the machine and fixed to the bottom of the motor frame 5|. As will be described further. below a switch enclosed inthe box controls the motor as well as an electric heating element 68 provided in the rinsing compartment 58, the conductors 69 of which element are led into said box through atube 18.- 1| represents the current carrying cable.

Fixed to a shaft 12 is 'a double-armed lever 13 which is located just underneath valve rods 56 and 59 and connected to each of said rods by links 14 and 15, respectively, a pin 18 on the lever 13 engaging an elongated slot 11 in the link, said shaft 12 being rotatably mounted in the wall of the control box 81 and carrying inside said box an operating member arranged to control the switch in a'. manner to be described further below. The arrangement is such that at each end position of lever 13 one valve is open and the other closed. A rope 18 is fastened at its ends to the ends of lever 13 and conducted over guiding rollers 19 to a switch panel 88 provided at the front of the machine housing and accessible through an aperture in the door 4la of the washing bench. This switchpanel carries a knob 8|, whose spindle 8la carries an arm 82'to the free end of which rope 18 is connected. When knob 8| is turned in one direction or the other, valves 55, 58 will accordingly be opened and closed alternatingly.

Another knob 83 provided on switch panel 54 carries on its spindle 8311 an arm 84 which is connected by .a rope 85 conducted over a guiding roller 88 to bell crank lever 81 controlling th valve rod 6! of the discharge valve of the washing pump 52 which valve is kept in the closed position by a spring. Mounted on the same shaft 83a inside the machine housing is an upwardly directed arm 89 which by a roller 90 engages the underside of the lid 45 and serves to raise said lid by a small angle, so that it can be gripped manually.

As will be described in further detail below, the switch is also arranged to be actuated by a thermostat comprising a bimetal body 8| arranged at the bottom of the rinsing compartment 58 and acting on a spindle 82 conducted through the wall of box 61 and carrying inside the box an operating member which acts on the switch. At its free end spindle 92 carries a button 83 accessible through an opening in door 4la.

As will be seen from Fig. 5 the control box 51 is fixed by screws 94 to the base of the electric motor frame 5|. The control box has an'elongated form and contains at one end a terminal block 85 for the motor and at the other end a switch indicated in its entirety by 96. In the embodiment shown the switch comprises a double pole two-way rocking switch with two mercury rockers '81, 88 each having two pairs of contacts. which are connected to the source of current. the motor and the heating element in the manner shown in Fig. 10.

According to the diagram shown in this figure the incoming conductors 1| are each connected to the inner'contacts 91b, 91c and 98b. 88c. res'pectively. of the contact pairs of the two rockers 91 and 98, respectively, .whilst the motor 5! is connected over conductor 99 to the outer con-' tacts 91a, 98a of one of the contact pairs and the heating element 68 over conductors ,68 to the outer contacts 91d, 88d of the other contact pair. Thus, the motor SI and the heating element 68 are connected in parallel to the switch.

common frame I00 with side plates IM and I02,

plate IOI being fixed to a hollow shaft I03 mounted in the control box and plate I02 mounted on a pin I00 fixed to shaft 12. Subject to the action of spring I05 the hollow shaft tends to turn frame I00 with rockers '91, 98 counter-clockwise as viewed from the right in Fig. 3. The motor conductors from and to the switch are conducted through the hollow shaft I03. ,By reason of the relatively large distance between switch 96 and terminal block 95 all risk of conductor breakage -'is avoided.

As already-mentioned above, valve rod 13 is fixed to the shaft 12, for example by a pin I08.

An arm I01 provided inside the box 61 is fixed to shaft 12 or formed integral therewith. 'At its free end arm I01 carries a roller I08 cooperating with a rocking lever I I0 pivoted on a pin I09 fixed to the wall of the control box, this lever having three recesses III, H2, H3, into which the roller i I08 engages in various positions. As mentioned above frame I00 with mercury rockers 91, 98' is 4 under the action of the spring I05 shown in Fig.

5 urged in counter-clockwise direction as viewed in Figs. 6 to 9, this rotation being limited by the engagement of a pin II4 provided on frame plate I02 with rocking lever IIO locked by arm I01.

In Figs. 6 to 8 valve rod 13 is indicated in dash lines 13a.

In the position of the switch as shown in Fig.

- 6, rinsing valve 58 is open and accordingly washing valve 55 closed. The motor is switched-on, that is to say the machine assumesrinsing position.

If the machine is to be set for washing, knob BI is turned in clockwise direction as viewed in Fig. 4, whereby lever 13 and hence also arm I01 are turned in counter-clockwise direction as viewed in Fig. 6; By this means rocking lever H0 and hence also frame I00 are releasedjthe latter being'under the action of spring I05 turned counter-clockwise carrying with it rocking lever I I0. In this way the motor circuit is broken. When lever 13 has attained horizontal position (see Fig. 7.) arm I01 will have rotated through an angle such that its roller I08 engages the cen-,

tral recess II2 of the rocking lever H0 and locks said lever in thisposition. whereby its pin H4 locks the switch in its left-hand end position in which the heating element circuit 68 is closed.

On turning lever 13 further arm I01 will be rotated through a further angle in counter- 1 clockwise direction, its roller I08 turning rocking lever H0 in clockwise direction until roller I08 engages the left-hand recess II3.,of lever IIII (see Fig. 8). During this rotation rocking lever I I0 by its pin II I turns the switch into its righthand end position, whereby the'motor circuit is again closed.

- At the commencement of the rotary movement of the lever 13 rinsing valve 58 can fall under its own weight, but washing valve 55 remains In this position roller I08 engages the :2 right-hand recess III in rocking lever H0 and the switch assumes its right-hand end position.

lever during which the motor can, be switchedrounded end of a bar II1 engages, said bar being eccentrically conducted througha disk. II8 on shaft 92 and secured inposition by a screw 'I I9. In this way the length of that portion of the bar I I1 lying outside the disk I I8 and hence the temperature at which the thermostat responds can be varied.

Shaft 92 or its extension carries inside thecontrol box 61 an arm I20 cooperating with'a stop I2I on frame I00. A spring I22 stronger'than spring I05 tends to turn shaft 92 and hence also arm I20 in counter-clockwisedirection in Fig. 9, stops I23, I24 fitted'on the wall of the box limiting the rotation of arm I20. v

In the system of operation of the switch as described above, it was assumed on setting handle 8I and lever 13 that the thermostat was switchedin as shown in full lines in Fig. 9, the temperature 'of the rinsing chamber, however, being less than that at which the thermostat responds. When this temperature is attained the'lower limb of spring I22 is turned in counter-clockwise direction in Fig. 9, arm I20 being thereby moved from the position shownin full lines in this figure into the position indicated by dash lines. In this new position of arm I20, the switch is on its setting checked in a central position in which it is without current and accordingly cannot be turned into its left end position, in which the heating element 68 is switched-on. By manual operation of knob '93, the thermostat may also be switched-on and off manually.

If the thermostat is switched-on but the tem-' perature is still too low, then on the setting of the valves 55 and 58 from washing into rinsing position or conversely, the switch will accordingly switch in heating element 68 when lever 13 assumes its horizontal position, but when the thermostat has been switched-on either manually by means of knob 93 or automatically under the action of the temperature in the rinsing compartment, then the switch will on setting of the valves provisionally be maintained in its currentless position (dash lines in Fig. 9), being prevented by arm I20 from assuming the position shown n Fig. '7, since spring I 22 is stronger than spring I05.

In the embodiment according to Fig. 11 the play of valve lever 13 is rendered possible in another way. At its lower edge lever is formedwith a guide surface I25 cooperating with a roller I26 at 1 the free end of an'arm I21 which constitutes the operating member of a two-way switch I28 and may be operated by aid of a lever I29. In this case the motor is switched-on in both contact positions of the switch. The curvature of the guide surfac I25 is such that in each rocking position of lever13 the end portion of the surface forms an arc with the pivot ,of arm I21 as a centre. The initial and final portion of the rotation of arm I21, during which the motor will be switchedon or off, accordingly exercises no action at all on lever 13, the roller I20. merely sliding along these arcuate portions. The lever will be adjusted only at the commencement of the second half of the rotary movement of arm I21, and the setting will again.

The invention is not limited to the embodiments shown which can be altered in several respects without exceeding the'scope of the invention. Of course, it is obviously not tied down to built-in machines of the type shown, but is also applicable with equal advantage to self-contained types of machines. As already stated the machine can be provided with one valve only.

What I claim is:

1. In a dish washing machine, two pumps the one for washing liquid and the other for rinsing liquid, a flow control valve for each of said liquids, an electric motor for driving said pumps. a switch for controlling said motor, means [or setting said valves so as to open and close them alternatingly. a manually operable control member, and means to connect said control member with the valve set-ting means and the switch so as to effect actuation of the valve setting means to open one of the valves, only whenthe switch is set to open the circuit of th motor. v

2. In a dish washing machine according to claim 1, wherein the means to connect the control member with the valve setting means and the switch comprises means to efiect actuation of the switch to close the circuit of the motor, only when said valve setting means is set to open one of the valves.

3. In a dish washing machine according to claim 1, wherein the means to connect the control member with the valve setting means and the of said lever.

switch comprises means to effect adjustment of the valve setting means from a position in which one of the valves is open and the'other closed, into a position in which the first-mentioned valve is closed and the last-mentioned valve open, only when the switch is set to open the circuit of the motor.

4. In a dish washing machine according to claim 1, wherein the switch is of the two-way type having two contact-making positions and an intermediate breaking path, the means to connect the control member with the valve setting means and the switch comprising means to open and.

close the valves alternatingly during the passage of the switch through said breaking path.

5. In a dish washing machine according to claim 1. wherein the switch is of the two-way type havingtwo contact-making positions and an intermediate breaking path, the means to connect the control member with the valve setting means and the switch comprising means to close the circuit of the motor at both contact-making p osilions and to open and close the valvesduring the passage of said switch through said breaking path.

6. In a dish washing machine according to claim 1, wherein the switch is of the two-way rocking type and the valves of the lift valve type.

the valve setting means including a rocking lever 7 connected with said valves so as to open and close them alternatingly, a pivot for said rocking lever, and means to operate the switch by the actuation TORD ERIK DANIEL BILDE. 

